Book Image

C Programming for Arduino

By : Julien Bayle
Book Image

C Programming for Arduino

By: Julien Bayle

Overview of this book

Physical computing allows us to build interactive physical systems by using software & hardware in order to sense and respond to the real world. C Programming for Arduino will show you how to harness powerful capabilities like sensing, feedbacks, programming and even wiring and developing your own autonomous systems. C Programming for Arduino contains everything you need to directly start wiring and coding your own electronic project. You'll learn C and how to code several types of firmware for your Arduino, and then move on to design small typical systems to understand how handling buttons, leds, LCD, network modules and much more. After running through C/C++ for the Arduino, you'll learn how to control your software by using real buttons and distance sensors and even discover how you can use your Arduino with the Processing framework so that they work in unison. Advanced coverage includes using Wi-Fi networks and batteries to make your Arduino-based hardware more mobile and flexible without wires. If you want to learn how to build your own electronic devices with powerful open-source technology, then this book is for you.
Table of Contents (21 chapters)
C Programming for Arduino
About the Author
About the Reviewers

Simulating analog outputs with PWM

As we know very well by now, it's okay to switch on/off LEDs, and as we are going to see in the next chapter, to switch on/off many things too by using digital pins as output on the Arduino.

We also know how to read states from digital pins set up as inputs, and even values from 0 to 1023 from the analog inputs from in the ADC.

As far as we know, there isn't analog output on the Arduino.

What would an analog output add? It would provide a way to write values other than only 0 and 1, I mean 0 V and 5 V. This would be nice but would require an expensive DAC.

Indeed, there isn't a DAC on Arduino boards.

The pulse-width modulation concept

The pulse-width modulation is a very common technique used to mimic analog output behavior.

Let's put that another way.

Our digital outputs can only be at 0 V or 5 V. But at a particular time-interval, if we switch them on/off quickly, then we can calculate a mean value depending on the time passed at 0 V or 5 V. This mean can easily...